Tapered optical fiber bundles can provide a low distortion method of magnifying or reducing an image. Used with a charge coupled device (CCD) sensor, tapered optical fiber bundles may be employed in medical radiography, fluoroscopy, and dental radiography, for enhancing images and reducing x-ray exposure times. Exemplary tapered optical fiber bundles are described in an article entitled "Fiber-optic Tapers Offer High-Quality Image Transmission" by Richard J. Weiss (http://192.149.147.16/web/oer/ february/feb97/research.html), which is incorporated herein by reference in its entirety.
Multiple CCDs may be arranged in an array to form a compound image sensor. Compound image sensor arrays may be utilized to capture images that are larger than a single CCD device can capture. Arrays of tapered optical fiber bundles may be utilized wherein each optical fiber bundle in the array is coupled with a respective CCD sensor. Tapered optical bundles may be required to compensate for gaps between adjacent CCD sensors and for electronics surrounding individual CCD sensors.
To provide coverage of a focal plane that is as nearly seamless as possible, precise alignment of adjacent optical fiber bundles in an array may be required. Abutting edges of adjacent optical fiber bundles may need to be mated within a tolerance of hundreds of microns in a single plane in order to produce substantially seamless images. Accordingly, the focal plane edges of optical fiber bundles may need to be carefully analyzed so that adjacent bundles can be mated as seamlessly as possible. As a result, conventional assembly techniques for precisely aligning adjacent optical fiber bundles within an array may be expensive and labor-intensive.
In addition, because of conventional manufacturing techniques, the edges of optical fiber bundles may be irregular and of poor quality. Consequently, precise, abutting alignment between adjacent bundles may not be possible. As a result, gaps may be present between adjacent optical fiber bundles in an array. These gaps may result in images having seams or other imperfections. In addition, because optical fiber bundles are conventionally molded or milled, the outermost optical fibers at the input face of a bundle may be damaged and thereby rendered optically inactive. Accordingly, portions of an image falling on optically inactive optical fibers within a bundle may not be captured by an image sensor coupled to the bundle. As a result, seams or other imperfections within the image may be produced.